The present invention relates to controlling of the position of the electrodes in arc furnaces.
It is known in the art to change the position of arc-furnace electrodes by means of hydraulic cylinders which carry a support whereon the electrodes are mounted. The cylinders receive their hydraulic working fluid via an electrically controlled valve interposed in the fluid line. An important safety problem with this state of the art is that any malfunction of the valve raises the possibility that it will become impossible to move the electrodes out of the melting zone, or even to maintin them in their operating position.